Railway-traffic-controlling apparatus



H. ZIERDT RAILWAY TRAFFIC CONTROLLING APPARATUS July 31, 1928'.

Filed. on. 2a, 1926 INVENTORI Patented July 31, 1928.

UNITED STATES 1,679,013 PATENT, OFFICE.

CONRAD H. ZIERDT, OF PENN TOWNSHIP, ALLEGHENY COUNTY, PENNSYLVANIA, AS- SIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYL- VAN IA, A CORPORATION OF PENNSYLVANIA.

RAILWAY-TRAFFIC-CONTROLLING APPARATUS.

Application filed October 23, 1926. Serial No. 143,618.

My invention relates to railway trafiic controlling apparatus, and particularly to apparatus of the type wherein current is periodically supplied to the track rails.

6 One feature of my invention is the provision of novel and improved means for periodically. supplying current to the track rails without contacts. I

I will describe three forms of apparatus embodying my invention, and W111, then point out the novel features thereof 1n claims.

In the accompanying drawing, Fig. 1 1s a diagrammatic view showing one form of apparatus embodying my invention. Fig. 2 1

ma diagrammatic view showing a modified form of apparatus also embodying my invention. Fig. 3 is a fragmental view showing a modification of a portion of the apparatus shown in Fig. 2 and alsoembodymg my invention. Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig; 1, thereference characters 1- and l designate the track rails of a railway which are divided into sections by means of insulated joints 2. These rails are supplied with alternating current by a transformer T, the secondary of which is constantly connected across the rails, a limiting impedance 3' being interposed between the secondary and the raill. The prlmary of the transformer T. is supplied with alternating current from the secondary of a transformer L, the primary of which is constantly supplied with alternating current om a source not shown in the drawing. Thesupply of current from the transformer L to the transformer T is controlled by a three-position relay'R having two windings 4 and 5 and three contacts 6, 7 and 12. When the relay R is de-energized, so that its back contact 6-6 is closed, the supply of alternating current from the transformer L to the transformer T and so to the track rails is stead-y. When, however, the relay R is energized in one direction or the other, the

' supply of alternating current from transformer L is periodically increased and decreased by the means which I will now describe. 7 a

' The reference character R -designates a variable reactor comprisin a core 8 having a large air gap, a winding 9, and a rotatable member 10 for varying the reluctanceof the airgap in the core 8. The member 10 is provided with teeth 11 which pass in closeproximity to the poles of the core 8, and these teeth are sospacecl iisters with one pole another tooth registers with the other pole. It follows that as the member 10 rotates, the reluctance of the air gap in core 8 will be periodically increased and decreased through a wide range, and so the reactance of the winding 9 will be periodicallydecreased and increased through a widerange. u i v The reference character R designates a reactor which is similar to reactor R except that the rotatable member 10 has half as many teeth 11 as the member 10 of. reactor R. It follows'that if the members 10 and'lO are rotated at the same speed, the variations 1n the reactance of the winding 9 will be at alower rate than the variations in the reactance of the winding 9. v

The members 10 and 10" are rotated at the same speed, and may conveniently be mounted on a shaft 15 which is connected through reduction gearing 18 with a motor M. This motor is supplied with current from the secondary of a-transformer L lthrough a contact 12 which is closed only when relay R is energized in one direction or the other, so that when the relay R is de-energized the motor M is at rest. V ',Assuming that relay R is energized in such direction that its contact 77" is closed, the. circuit for the primary of transformer T is from the. right-hand terminal of the secondary of transformer L, through wlnding 9 of reactor R contact 7-7, and the primary of transformer :T to the left hand terminal of the secondary of transformer L. WVinding 9 of reactor R is then placed on short circuit by contact 77 so that only the winding 9 ofreactor R is effective, and thus the alternating current supplied to the track rails 1 and .1 1S periodically increased and decreasedat a relatively high rate.

isenergized in such direction that its Contact 7-7: is closed, winding 9 of reactor R is placed on short circuit bythis contact and windin'g 9 of reactor R is included. in the circuit for the primary f that when one tooth reg- When, however, relay 4 transformer T, so that the alternating current supplied to the track rails is periodically increased and decreased at a relatively low rate.

Referring now to Fig. 2, the apparatus shown in this view is similar to that shown in Fig. 1, except that the variable reactor, which is here designated R comprises a ring-shaped core 8 having diametrically opposite inwardly projecting poles 13. The winding 9 for this reactor is made up of two coils which are located on the core and opposite sides of the line through the poles 13, 13 "and this winding is interposed between the transformer L and the'transformer T. The movable mcmberof the reactor B which is designated 14L, is mounted to rotate onan axis which passes through the center of the ring-shaped core 8 and is elongated so that it periodically increases and decreases the reluctance of the air gap between the two poles. Thismember l t-is attached to a shaft 15 which is connected through reduction gearing 18 with motor M. As shown in this view, a condenser 17 is connected in multiple with the winding 9 ofreactor R and the'condenser and winding 9 are preferably tuned to resonance at the frequency of the alternating current supplied by transformer L when the reluctance of winding9 is maximum. The condenser 17 materially increases'the ratio between theiinaximuna value and the mi1nimum value of the alternating current supplied to the rails 1 and 1 It is, of course, understood that a plurality of reactors may be provided in Fig. 2, thereby providing for different rates of variation of the alternating current supplied. to the track rails, and it will also be understood that these reactors and the motor M may be controlled by a relay in a manner similar to that shown in Fig. 1;

Referring now to Fig. 8, the apparatus is the same as that shown inFig. 2, except that the condenser 17 is connected in series with the winding of reactor R a step-up transformer 19 being provided, if necessary. In this form the series circuit including the condenser 17 and the winding of reactor R is tuned to resonance when the reactance ofthe winding 9 is at itsminimum value.

Although Ihave herein shown and described only three forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described 'my invention, what I claim is:

1. In combination with the rails of arailway trackand a'source of alternating current connected therewith, a reactor interposed in said connection and'having a core provided with an air gap, and movable means for periodically varying the reluc tance of said air gap.

2. In combination with the rails of a railway tracl; and a source of alternating current connected therewith, a reactor interposed in said connection and having a core provided with an air gap, an electric motor, and means operated by said motor for periodically varying the reluctance of said air gap.

3. In combination with the rails of a railway track and a source'of alternating current connected therewith, a reactor interposed in said connection and having a core provided with an air gap, a rotatable member of magnetizable material having teeth which pass in close proximity to the said core, and a'motor'for rotating said member. I

4. In combination with the rails of a railway track and a source of alternating current connected therewith, a reactor interposed in said connection and having a core provided with an air gap, a movable member for periodically reducing and: increasing the reluctance of said air gap.

5. In combination. with the rails of a railway track and a source of alternating current connected therewith, a reactor interposed in said connection, and movable means for periodically varying the effect of said reactor to thereby periodically increase and decrease the amount of current supplied to the track rails.

6. In combination with the rails of a railway track and a source of alternating current connected therewith, two reactors, means associated with one reactor for periodically varying the effect thereof at one rate, means associated with the other reactor. for periodically varying the effect thereof at a different rate, and means for interposingone ofrsaid reactors orthe other in the connection between saidsource and the traclc rails.

' 7 In combination with the rails ofa railway. track and a source of alternating cur rent. connectedtherewith, a reactor interposed in saidconnecti-onand having a core provided with an air gap, and means for periodically varying the reluctance of said air gap to thereby periodically vary the amount of current supplied to the rails from said source.

8. In combinationwiththe rail ofa rai1- way track and a source ofalternating current connected therewith, a reactor interposed in said connection, and movable means .for periodically varying the effect of said.;reactor to thereby periodically increase and decrease the amount ofcurrent supplied to thetrack rails, and a condenser associated with said reactor.

9.. Incombination with the rails of emailwaytrack. anda source ofalternating current connected therewith, a reactor interposed in said connection, movable means for periodically varying the effect of said reactor to thereby periodically increase and decrease the amount of current supplied to the track rails, and a condenser connected in multiple with said reactor.

10. In combination with the rails of a railway track and a source of alternating current connected therewith, a reactor having a ring-shaped core provided with diametri cally opposite inwardly projecting poles, a winding made up of two coils located on said core on opposite sides of the linethrough said poles and interposed in the connection between said source and one of the track 7 rails, a member of magnetizable material mounted to rotate on an axis passing through the center of said core and to periodically reduce and increase the reluctance of the path between said poles, and means for rotating said member.

11. In combination with the rails of a railway track and a source of alternating current connected therewith, a reactor interposed in said connection, and movable means for periodically varying the impedance of said reactor.

In testimony whereof I afiix mysignature.

CONRAD H. ZIERDT. 

